Credit card and indentity verification system

ABSTRACT

An improved form of credit or identification card and a system for verifying the propriety of ownership thereof. The card comprises, in addition to the conventional embossed indicia which ordinarily includes a name and an account number, a laminated or encapsulated center layer of material upon which is deposited an electrical circuit consisting of a matrix of electrical conductors and semiconductors coupled to a plurality of contact points. At least three of the contact points are coupled to certain ones of the semiconductor devices thereby providing a code number unique to each card and the remaining contacts are coupled to other parts of the circuit to give a false code. A card verifier has a like plurality of electrical contacts adapted to engage the card contacts and a plurality of selectors for selectively coupling the circuit in the card with a circuit in the verifier so as to produce a YES or NO output signal to verify selection of the proper code number.

ist-aeeioail United St 1 Chavez 1 1 CREDIT CARD AND INDENTITYVERIFICATION SYSTEM [76] Inventor: Robert C. Chavez, 1764 IndustrialRd., Las Vegas, Nev. 89102 [22] Filed: June 4, 1973 [21] Appl. No.:366,762

Related U.S. Application Data [63] Continuation-in-part of Ser. No.157,928, June 29,

1971, abandoned.

52 us. c1. ..235/61.7B,235/61.11A,

7., 5/ N. 49/149 A 51 1m.c1 ..G06k 5/00,GO6k 7/O6,G06k 19/06 [58] FieldofSearch ,..235/61.7 B, 61.11 A, 61.11 C,

[ Feb. 25, 1975 FOREIGN PATENTS OR APPLICATIONS 851,357 9/1970 Canada235/617 B Primary ExaminerDaryl W. Cook Attorney, Agent, or Firm& LyonLyon [57] ABSTRACT An improved form of credit or identification card anda system for verifying the propriety of ownership thereof. The cardcomprises, in addition to the conventional embossed indicia whichordinarily includes a name and an account number, a laminated orencapsulated center layer of material upon which is deposited anelectrical circuit consisting of a matrix of electrical conductors andsemiconductors coupled to a plurality of contact points. At least threeof the contact points are coupled to certain ones of the semiconductordevices thereby providing a code number unique to each card and theremaining contacts are coupled to other parts of the circuit to give afalse code. A card verifier has a like plurality of electrical contactsadapted to engage the card contacts and a plurality of selectors forselectively coupling the circuit in the card with a circuit in theverifier so as to produce a YES or NO output signal to verify selectionof the proper code number.

19 Claims, 10 Drawing Figures PAIENIEE I975 3. 868 057 am 1 or d Q R 2 WW 0 w w /W F E w E CREDIT CARD AND INDENTITY VERIFICATION SYSTEM This isa continuation-in-part of my previous application, Ser. No. 157,928filed June 29, 1971, now abandoned.

BACKGROUND OF TI-IE INVENTION The present invention relates generally toa credit card system which makes possible the virtual elimination ofcredit card misuse. The ensuing description deals with the use of theinvention as a credit card, although it will be apparent that potentialscope of the invention would include any use as a positive means ofidentification. The advent of credit cards for the convenientacquisition of goods and services in lieu of the use of currency hascarried with it considerable problems in what may be generally calledcredit card misuse. Misuse of credit cards includes the use by others ofcards which have been either lost or stolen, unpremediated felonioususers who have received unsolicited credit cards in the mail, but whodeny having used them, outright counterfeiting of credit cards, and theuse of cards by the rightful owner thereof beyond the agreed creditlimits. In such cases, substantial financial liability may be borne byeither the credit card holder, the credit card company or both, andrecent reports have indicated that losses sustained on account of creditcard misuse total in the hundreds of millions of dollars annually. It issubmitted that such losses are sustained as a direct result of the factthat credit card misuse is relatively easy to commit by those persons sodisposed because of the lack of a positive and easy means ofidentification.

Most credit cards currently in use have a place for the signature of theauthorized user but this proper signature is seldom, if ever, checked orcompared with the actual users signature because the clerks handling anindividual transaction are not competent to analyze the handwriting.Other credit cards currently in use have a picture of the authorizeduser but again this is not a positive means of identification, it is aninconvenience when the rightful user desires to permit another to usehis card, and it certainly does not prevent counterfeiting. Othermethods of positive identification have been proposed, such as afingerprint check or a magnetically-encoded strip of material on thecard which can be read by an appropriate card-reading device but thesesystems are very costly to implement.

SUMMARY OF THE INVENTION The foregoing shortcomings may be eliminatedthrough the use of the present invention inasmuch as the credit cardherein proposed is provided with a secret code number which shall beknown only to the rightful user thereof. When the holder of the creditcard desires to use it, it is inserted in a verification device and therightful user thereof selects by means of appropriate control on theverification device the code number known only to him and when heselects the proper series of numbers, there will be a visual indicationthat the number encoded on the card corresponds with the number selectedby the card user. Obviously, not knowing the proper number, one whofinds or steals the card will not be able to use it. The manner in whichthe code number is encoded on the card makes it extremely difficult toascertain the correct code number.

In one embodiment the credit card containsa matrix of contact points,ideally a hundred or more and each contact point can then be assigned acode according to a numerical or alpha-numerical system. Each of thecontact points is interconnected with the other by thin deposits ofelectrical conducting material but rather than being directly connectedto one another each of the points is electrically connected to a smalldeposit of semiconductor material which in the form of diode provides afinite electrical resistance between any two points. Three or more ofthese contact points are not interconnected in the mannerjust describedbut in turn are electrically connected to a semiconductor device havingthree or more terminals, such as a transistor. The contact points whichare connected to the semiconductor device are selected at random in thematrix.

It is these three or more points which determine the unique code numberfor the individual card, as deter mined by the coding system. I

The card verification device contains a plurality of sensing devicesadapted to contact the contact points on the card when the card isinserted in the device. The verification device also contains a numberof selectors by which the card user selects the contact pointscorresponding to the code or index number so that the deviceelectrically connects to the three or more terminals which communicatewith the semiconductor device. By this method, the semiconductor deviceis coupled to a circuit in the verification device so that an electricalcircuit is completed whereby current will be conducted to indicate aproper selection of code num bers. If the incorrect number is selected,the circuit within the verification device will not be properlycompleted and an error signal will result. The interconnection of all ofthe unused contact points through semiconductor material renders itextremely difficult to ascertain the proper code number inasmuch asresistance measurements made upon the card using an ohmmeter, forexample, will provide confusingly false readings between any two contactpoints whether the meter is attached to the proper contact points ornot. Thus, resistance measurements made upon all of the contact pointstrying all of the various combinations will not permit a wrongfulpossessor of the card to determine the proper code number.

In a modified form of the invention a unique coding circuit employing aseries of SCRs is embedded in the card and due to the configurationofthis circuit the number of contact points on the card, and thereforein the verifier as well, is reduced to a small number. This circuitstill provides a very large number of possible combinations while alsoproviding false code indications if effort is made to decode the same.

It is an object therefore of the present invention to provide a creditcard and a credit card verification device whereby improper use can besubstantially eliminated.

It is also an object of the present invention to provide an improvedcredit card system whereby the proper owner of a credit card may utilizeit without fear of financial liability on account of loss or theft andin addition permitting the credit card company to utilize the cardverification device for accounting purposes.

It is a further object of the invention to provide a credit cardverification system which will substantially facilitate the recovery oflost or stolen cards.

Further objects and advantages of the present inven tion will be readilyapparent upon reading the ensuing detailed description in conjunctionwith the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a pictorial representation of aform of a credit card verification device showing a credit card inassociation therewith.

FIG. 2 is an exploded perspective view of a credit card made inaccordance with one embodiment of the present invention.

FIG. 3 is an enlarged sectional view showing the relationship of thecredit card verifier and the credit card.

FIG. 4 is an enlarged plan view of one embodiment of the intermediatelayer showing the matrix arrangement and semiconductors thereon.

FIG. 5 is a circuit diagram of one embodiment of the electrical portionof the credit card verifying device.

FIG. 6 is a plan view of the intermediate layer of the card showinganother embodiment thereof employing a NAND gate.

FIG. 7 is another circuit diagram for an alternative electrical portionof the card verifier.

FIG. 8 is the equivalent circuit for the NAND gate employed in FIG. 6.

FIGS. 9a and 9b are circuit diagrams of another embodiment of thepresent invention showing an improved and simplified coding circuit forthe card in FIG. 9a and a simplified code selection and verificationcircuit in FIG. 9b.

DESCRIPTION OF THE FIRST EMBODIMENT As shown in FIG. 1, the new creditcard generally designated 10 comprises three initially separate layersof material which are subsequently permanently bonded together. As isthe current practice, the materials used in the three separate layersmay be any suitable, somewhat rigid plastic. The top layer 12 would havethe same general appearance as do most credit cards today including thename 13 of the credit card holder, his account number 14 and an insigniaor name indicating the credit card company as represented by the design15. The name 13 and the account number 14 are ordinarily embossed on thesurface of the card and provide a means for imprinting the name andaccount numberon invoices. When constructed in this manner, the creditcard of the present invention is compatible with credit card imprintingdevices currently in use but it is contemplated that the credit cardverification device disclosed herein may also incorporate the details ofcredit card invoice printing devices although it is not deemed necessaryto show the details of such construction inasmuch as they are well knownin the art.

The bottom layer of the card 16 is a substantially flat member with noraised or embossed indicia thereon but is provided with a plurality ofspaced apertures 18 which are symmetrically located over the entiresurface of the bottom layer 16 in a grid or matrix fashion defin ing asystem of coordinates. The purpose of the apertures 18 is to provideaccess to contact points in the interior of the card as will soon bereadily apparent.

The middle layer or lamina 20 is also a substantially flat, thin pieceof pliable plastic material which is electrically nonconductive as arelayers 12 and 16. on the surface oflamina 20 which when bonded will befacing the bottom layer 16 there is deposited or etched a plurality ofelectrical contact points 22. Contact points 22 are symmetricallyarranged on this surface of layer 20 in the same manner as are theapertures 18 in layer 16 providing a system which can be described bynumerical or alpha-numerical coordinates and these contact points arepositioned to coincide with apertures 18. As shown in FIG. 2 and morecompletely in FIGS. 4 and 6, deposited on the surface of lamina 20 are aplurality of diodes 24. Each of the contact points 22 is connected toone or more of these diodes by means of conductor paths 26 which arealso etched upon the surface of lamina 20. The diodes are thus connectedin strings, the polarities being alternated at random, and the stringsnot necessarily connected together. The excep tion to the foregoingstatement is that three or more of these contact points will not beinterconnected to these diodes but will be connected to a semiconductordevice.

FIG. 4 shows one embodiment of the invention in which the semiconductoris a unijunction transistor 28 deposited upon a surface of intermediatelayer 20 which can be made, according to present technology very smallso as not to provide a bulky area or excess thickness in the card.Unijunction 28 has an emitter electrode 30, and two base electrodes 32and 34. Each of these electrodes is connected through an etched-oncircuit path, respectively to selected ones of the contact points 22a,those contact points being ones which are not interconnected to any ofthe diodes 24. As shown in FIG. 4, in which the set of coordinatesestablished by the contact points is numbered from left to right, it isshown that the emitter electrode 30 is connected to the contact pointindexed No. 56, the base electrode 32 is connected to the contact pointindexed No. 22 and the other base electrode 34 is connected to thecontact point indexed No. 108. Thus, the code number established by thecoordinates for the card shown in FIG. 4 is the number 56-22-108.

Turning now to the details of the card verification device, this ispictorially represented in FIG. 1 and indicated generally by the numeral40. The device 40 in cludes a slot 42 into which the card to be verifiedshall be inserted. It would be desirable, in order to assure that thecard is properly inserted in the slot 4-2 to provide the card with somesort of indexing means. It should be obvious that because the contactpoints are indexed according to a certain numerical order, it isnecessary that the card not be reversed. Thus, the card could have anotch cut in one end as shown at 41 in FIG. 1 which would permit thecard to be inserted all the way into slot 42 there being an embossment43 (See FIG. 3) which would be received in notch 41 to permit the cardto be inserted all the way. The exterior of the card reading device hasa number of selector knobs on the exterior thereof. The first series ofknobs 44, 45 and 46 are multiple position rotatable switches used toselect an index number. Another series of knobs 47, 48 and 49 are againmultiple position switches having three or more positions which selectwhich set of the series of numbers in the combination shall correspondto the number selected by the corresponding number selection switch. Inother words, in order to prevent someone from learning the combinationof the credit card, the user may select switch 48 to be the first digitwhereupon he will set that to the first digit position and then set dial45 to his first number, in our case that being number 56 then he mightselect the knob 47 to be the second digit whereupon he will adjust knob44 to number 22, and so on. After having properly adjusted all of theseknobs, the card holder or the attendant depresses button 50 and if theproper card has been properly inserted and the numbers properly selectedas aforesaid, an indicator light 52 will be lighted indicating andthereby verifying that the card holder is in possession of a propercard.

As previously described, bottom layer 16 of the card is provided with aseries of apertures 18. In FIG. 3, the card is shown inserted in slot 42with the bottom layer 16 facing downwardly. In the interior of slot 42there is positioned a plurality of contact members 54 herein shown aselectrically conducting spheres. The contact spheres 54 are held inplace by a perforated plate 56 having apertures 58 therein, the diameterof which is slightly less than the diameter of spheres 54. The spheresare biased upwardly by springs 60 which also provide electricalconducting paths and to which are connected conductor leads 62. Itshould be apparent that when card 10 is properly inserted all the way inslot 42 all of the contact spheres 54 will reside in the apertures 18providing electrical connections to each contact point 22.

FIG. 5 shows one embodiment of an electrical circuit diagram containedin the card verification unit 40 specifically a circuit to operate inconjunction with the unijunction device shown in FIG. 4. The threecoordinate number selecting switches 44, 45 and 46 are shown with thecontacts being dependent upon the number of contact points designed tobe on each card. To the contact points 64 are connected the conductors62 which connect to the spring contacts as previously described. Itshould be apparent that all of the contacts 64 assigned No. l areconnected to spring contact No. 1 and so on. The Wiper 66 of selectorswitch 44 connects through condctor 68 to one of the terminals of eachof the digit selector switches 47, 48 and 49. Likewise, the wipers ofthe other number selecting switches 45 and 46 connect to correspondingterminals'on digit selector switches 47 and 48.

Assuming the digit and number selectors are properly set, line 72connected to wiper 70, will be coupled to the emitter of unijunction 28,line 74 connected to wiper 76 will be coupled to one base 32 and line 78connected to wiper 80 will be coupled to the other base electrode 34.Conductor 72 is connected to junction point 82 between capacitor 84 andvariable resistor 86 which are coupled in series. Capacitor 84 isconnected to the negative ground bus 88 to which is connected thenegative terminal of battery 90. Resistor 86 is coupled through positivebus line 87 to push button switch 92, relay contact 98a and power switch94 to the positive terminal of battery 90. Line 74 is connected throughseries resistor 96 to positive bus line 87. Line 78 is connected to oneside of relay coil 87. Line 78 is connected to one side of relay coil 98the other side of which is connected to negative bus 88. Relay coil 100is coupled in series with resistor 102 between negative bus 88 andpositive bus 87. Relay contact 100a is normally open (operated inresponse to current in relay coil 100) is coupled across switch 92.

Lamp 104 is coupled in series with relay contacts 98b and b, both ofwhich are normally closed, between negative bus 88 and positive bus 87.Lamp 106 is coupled in series with relay contact 100a, which isnormallyopen, between negative bus 88 and positive bus 87. In thisconfigurations as properly connected to the unijunction transistor, thecircuit is a relaxation oscillator, lamp 104 indicating when powernormally open on and lamp 106 indicating proper interconnection Of theunijunction into the oscillator circuit.

Following are typical types and values of the circuit elements employedin this circuit:

2N 16718 Texas Inst. I00 Microfarad Unijunction transistor Capacitor 8426.5VDC, 700 Ohm 24 VDC Power supply When power switch 94 is closed,lamp 104 lights indicating the system is ready. The DC voltage isapplied across the push button switch 92 which when depressed appliescurrent through relay coil 100 closing contactsl00a across the switch92, and opening contacts 10% with the result that lamp 104 goes out. Atthe same time contacts 100a close turning on lamp 106. Release of switch92 will not change this condition. DC power will also be applied to baseelectrode 32 through resistor 96 and current will also flow throughcapacitor 84 starting it to charge. After a specific time determined bythe values of resistor 86 and capacitor 84, the charge on the capacitorwill bias the emitter 30 sufficiently to cause unijunction 28 toconduct. When it conducts, capacitor 84 discharges through baseelectrode 34 and through relay coil 98. The current through coil 98being sufficient to momentarily energize the relay, contacts 98a and 98bboth open, cutting off current to relay 100 and thereby returning theentire circuit to its original state.

The flashing sequence of lamps 104 and 106 indicates proper connectionof the card into the circuit. If lamp 106 is green and lamp 104 is red,the sequence will be first a green light, then upon depressing switch 92a red light for a preset time, followed by a green light again.

Improper connection of the card contacts into this circuit will causeeither no change in the initial green light signal or other sequencesall indicating wrong code selection. For example, if conductors 74 and78 were connected across a diode of the wrong polarity, relay 100 wouldenergize turning on the red lamp, but relay 98 will never energize sothe red lamp will remain lit. If conductors 74 and 78 were conductedacross a diode of proper polarity both relays will energize but contact98a will keep opening and closing causing lamps 104 and 106 to continueblinking on and off as long as switch 92 is depressed. The same actionwill occur if conductors 72 and 74 are coupled across a diode of eitherpolarity. Relay 98 will never energize, thus keeping the red lamp 106on.

The chains of diodes 24 to which the unused contact points are connectedprovide a means for giving erroneous electrical readings between theinactive contact points so that someone trying to electrically determinethe combination number through resistance measurements would not be ableto do so. Resistance measurement between contact points will indicateeither a small finite resistance representing the forward resistance ofthe diodes (about 200 ohms) or the unijunction or an open circuitindicative of the back resistance of one or more diodes or theunijunction. The forward resistance of the unijunction is E to Bapproximately 200 ohms, E to B 600 ohms and I? to B infinite Toeffectively decode the card would take a three element resistance checkand it should be recalled that there are over one million possiblecombinations. With all of these measurements. it is clear that theinvestigator has determined nothing about the location of the propercontact points. A card containing 100 electrical contact points, ofwhich three are active, provides one million possible combinations.Since the correct selection of the switches 47, 48 and 49 is alsorequired, this multiplies the number of possible combinations by three.Four terminal semiconductor devices are also available which if usedcould raise the number of possible combinations to three hundredmillion.

FIGS. 6 through 8 set forth another embodiment of the invention ofa moresimplified form. Here, the operative semiconductor element comprises aNAND circuit 120 deposited upon the intermediate lamina 20. NAND circuit120 has input terminals 121 and 123 which are coupled to unused contactpoints 122 and 124 respectively, and an output terminal 125 connected tocontact point 126. In addition, the NAND circuit requires biasing, sothe positive or B+ terminal is connected to contact point 128 and thenegative or B- terminal is connected to contact point 130. because allcards using a NAND circuit will require this biasing, contact points 128and 130 may preferably be additional to the contact points making up theencoding grid and may be situated along the edges of the card. Locationof the biasing contacts within the encoding grid would of courseincrease the number of possible code combinations but may make falsereadings possible.

In FIG. 7, the switching apparatus previously described in connectionwith FIG. schematically designated by the boxes 132, 133 and 134inasmuch as the details thereof are the same. Switches 132 and 133couple the inputs 122 and 124 through a push button switch 136 to a DCpower supply 138 the output of which may be aslow as 1 VDC. The outputterminal 126 is coupled through switches 134, through Zener diode 140,to indicator lamp 142 to the negative terminal 144 of supply 138. Thenegative supply terminal 144 couples directly to the card 8- terminal130. The positive supply terminal 146 of approximately 4 VDC is coupledthrough power switch 148 to the 13+ terminal 128. power lamp 150 iscoupled across switch 148 and negative supply terminal 144.

When switched on, lamp 150 preferably green is it. If the proper contactpoints the card are selected, depression of switch 136 will produce anoutput at terminal 126 of sufficient amplitude to cause Zener diode 140to conduct, causing indicator lamp 142 to light, signifying a propercode selection. Zener diode having a Zener level of about 3 VDC willprevent improper input connections from causing lamp 142 to light sincethe input signals are only about 1 VDC.

FIG. 8 is the equivalent circuit of a typical NAND gate employing twotransistors and appropriate biasing resistors. It will be readilyapparent that resistance measurements made attempting to decode a cardwill not be fruitful because the overall diode matrix will producesimilar results. With the NAND gate biasing points separate from theencoding matrix, it cannot be shorted to the output, so a false readingcannot occur in that way either.

FIGS. 9a and 9b set forth an improved embodiment of the presentinvention in that the circuitry therein shown provides the previouslydiscussed feature of having a single unique code sequence for a cardtogether with the provision of false code indications so that the cardcannot be easily decoded but this embodiment permits the reduction ofcontact points on the card, and therefore on the card verifying unit toa very low number while still permitting an extremely large number ofpossible code combinations. The obvious advantage of reducing the numberof contact points is that it will reduce the number of possiblemechanical failures in reading or verifying cards. It is apparent thatfor a large number of contact points, it is possible that one of theimportant contacts may become dirty and fail to make the properelectrical contact with the verifier unit, or the spring loaded contactsof the verifier unit may, upon continued usage, suffer some mechanicaldefect which could result in wrongly failing to properly verify a goodcard. It is important that the card verifiers be dependable so thatcustomers who use them and proprietors who have them can maintain a highdegree of confidence in them.

The verification unit, the circuitry of which is shown in FIG. 9b may beconstructed in virtually any configuration, it being necessary only thatthere be provided the number of contact points to be hereinafterdiscussed together with a number of momentary contact switches or pushbuttons and a pair of multi-positioned rotary switches. It will be seenfrom the ensuing discussion that the power supply requirement of thisparticular circuitry is extremely low so that the unit can be small,portable and self contained. The verification unit consists of 14contact points generally designated in FIG. 9b by the numeral 200 andthese contact points are indexed by the digits 0 through 9, letters A"and B" and signs and Each of the contact points 200 is coupled to oneterminal 202 of momentary push button switches 204. A first rotaryswitch 206 has a wiper arm 208 and a plurality of contacts 210. A secondrotary switch 212 is similarly provided with a wipe arm 214 and aplurality of contacts 216. The switch contacts 210 and 216 have, inaddition to of positions to which no connections are made, connectionsindicated by the arrows and numered from 0" to 9 which are coupled inturn to the terminals 202 of the push button switches 204 numbered 0through 9 and A" and B so that contacts 210 and 216 are coupled inparallel to the correspondingly numbered push button switches, such asone-one, two-two, etc. The exception to the foregoing manner ofconnection is that one of the contacts 210a, which may be any of thenumbered contacts 210 is coupled through conductor 218 to terminal202aof push button switch 2040, which is in turn also coupled to thecontact designated by the letter A. Similarly, one of the contacts 21Gbof rotary switch 212 is coupled through conductor 220 to terminal 20217of push button switch 204b, that terminal also being coupled to thecontact indexed with the letter B.

A power switch 222 has one contact coupled to a source of positive DCvoltage, herein designated as the B+ terminal 224 and, for example, thevalue of the 13+ voltage is indicated as 10.5 volts DC. The otherterminal of switch 222 is coupled to ground terminal 226. All of thepush button switches 204 have their other terminals tied to a common busline 228 which in turn is coupled to conductor 230 to the base electrode232!) of transistor 232. The collector 2320 is coupled through anappropriate biasing resistor 234 to the B+ line 235. The emitter 232e islikewise coupled to the B+line 235 through biasing resistor 236, as isthe base electrode 232b coupled through resistor 238. The emitter 232eis similarly coupled through resistor 240 to conductor 242 which isconnected to the wiper 214 of switch 212. The wiper 214 is also coupledthrough a conductor 244 to the grounding terminal 226 of switch 222. Thecircuit also includes a capacitor 246 coupled between base electrode232b and ground conductor 242.

The emitter 248e of transistor 248 is connected directly to the B+ line235, the collector electrode 2480 is coupled to the wiper 208 of rotaryswitch 206. Thus, power is supplied to the circuit upon the closure ofswitch 222 so that positive potential is applied through line 235 totransistor 232 and 248, a common ground for the circuit being coupledthrough switch contacts 226 to the wiper of switch 212, and in theconfiguration shown in FIG. 9b,ground will be supplied through conductor220 to the contact point B coupled to push button switch 202b. Whenpower is applied to the circuit, the base of transistor 232 goespositive and supplies approximately I /2 volts on the bus line 228 toall of the switches 204. The collector of transistor 248 also goespositive supplying plus 10.5 volts to the wiper 208 and throughconductor 218 to the contact terminal 202a. Thus, in the configurationof the circuit shown in FIG. 9b, the unit provides a1 V2 volt triggersignal to all of the 14 contacts; and, through the selector switches206, 212, anode voltage of plus 10.5 volts to any one of the contacts,and ground potential to any other one of the contacts. The indiciaherein given to the various contacts are for the purpose of explanationand it is equally possible that other numerical systems oralphanumerical systems may be adopted for the contacts other than theand or the other indices herein indicated.

Turning now to FIG. 9a, there is shown a plurality of silicon controlledrectifiers (SCR), there being 14 in number. Of those 14 SCRs, six areemployed for the purpose of providing a false code signal, seven areemployed to establish a six-digit code and a final SCR is used tocontrol the function of an output indicator. SCRs 250, 252, 254, 256,258 and 260 each have their gate electrodes connected directly to thecontact points on the card herein designated by the index digits 1, 4,6, 5," 7 and respectively. These gate electrodes are likewise coupledthrough resistors 251, 253, 255, 257, 259, 261 to the card common groundbus 262 which is in turn coupled to contact point 264 indexed B. Theanodes of SCRs 250-260 are all coupled in parallel and connected to B+conductor 266, which is in turn coupled to contact point 268 hereindesignated A." The cathodes of SCRs 250-260 are coupled in parallel andconnected to conductor 270. SCRs 272, 274 and 276 are coupled in serieswith the anode of SCR 272 coupled to 8+ line 266. The gate electrodes ofSCRs 272, 274 and 276 are connected directly to contact points on thecard herein designated by the digits 2, and 8". These gate electrodesare likewise coupled through resistors 273, 275, 277 respectively toground bus 278 which is in turn coupled to the other ground bus 262.Resistors 280, 281 and 282 are coupled between the cathodes of SCRs 272,274 and 276 respectively and ground, to keep each SCR conducting afterremoval of its respective trigger signal until the next successive SCRis made conductive.

Another SCR 282 has its anode coupled to B+ line 266 and its cathodecoupled in series with SCRs 284, 286 and 288. The gate electrode of SCR282 is coupled through a resistor 290 to the cathode of SCR 276. Thegate electrodes of SCRs 284, 286 and 288 are connected directly tocontact points on the card herein given the index digits 3," 9" and 0".As with SCR 272, SCRs 284, 286 and 288 are provided with resistorscoupled between the gate electrodes and ground and between theircathodes and ground, with the exception SCR 288 the cathode of which iscoupled to one terminal ofa light emitting diode 290 the other terminalof which is coupled through resistor 292 to ground. An additional SCR294 is connected across the light emitting diode 290, with its anodecoupled to the cathode of SCR 288, and the cathode of SCR 294 coupled tothe junction between the diode 290 and resistor 292. The gate electrodeof SCR 294 is coupled through resistor 296 to conductor 270 and throughresistor 298 to ground.

The index digits mentioned herein as assigned to the contact points onthe card are given for illustrative purposes only, it being understoodthat the indexing of the card contacts may be done so as to provide anycombination of digits. Here, the first two digits of the combination aredetermined by the switches 206 and 212 and the positions of thoseswitches which provide the utputs to contacts A" and B. With referenceto FIG. 9b, it will be indicated that the positions of those two rotaryswitches would correspond to index digits 5 and 3 for letters A" and Brespectively. In this manner, proper connection of those terminals tocontacts A" and 8" will provide appropriate 13+ and ground terminals tocontacts 268 and 264 on the card. The third, fourth and fifth digits inthe code will be represented by index digits 2, and 8 and the remainingdigits in the code number will be determined by the connections of thegate electrodes of SCRs 284, 286 and 288, here shown to be assigned thedigits 3, 9 and 0." Thus, the combination of the card shown in thedrawings is AB2-8390.

When the proper combination of the card is known, and the card isinserted in the verification unit until all contacts are properly made,the rotary switches 206 and 212 are moved to the proper positions, herepositions A and B or 5 and 3 respectively. Power switch 222 is closedand the verification unit will thereby provide a positive anode voltageat contact A and a ground connection to contact B, plus an SCR triggervoltage available at each push button switch through common bus 228.Anode voltage is provided to all of the SCRs 250260, 272 and 283. Thetrigger voltage is available to each gate of each SCR through thecontacts except of course the gates to SCRs 283 and 294. The next sixdigits of the combination are introduced into the card by pushing theproper push buttons in the correct sequence, in this case 2-8390." Whenpush button 2 is depressed, a trigger voltage is applied to the gate ofSCR 272 causing current to flow through the SCR and through the cathoderesistor 280 to ground so that SCR 272 is turned on and maintained inthat condition, at the same time supplying anode voltage to SCR 274.When the dash or minus button is depressed, SCR 274 will be turned on ina similar manner supplying anode voltage to SCR 276 which is in turnturned on by depression of push button corresponding to that number. Theresistors coupled between the gates of the SCRs to ground desensitizethe gates so that they will not trigger the SCRs in the event there is astray noise. When SCR 276 is turned on it turns on automatically SCR 283thereby enabling SCR 284 and supplies to the anode of SCR 284 the fullanode voltage. It has been found that due to junction voltage dropsoccuring between the anode and cathode of an SCR, where SCRs arecascaded, the voltage drop is too great if more than three SCRs arecoupled in series. Accordingly the series combination of SCR 272, 274and 276 is provided to trigger the intermediate SCR 283 which therebysupplies full anode voltage to the next successive series of three SCRs.Then, when push buttons 3," 9" and are depressed, each of thecorresponding SCRs 284, 286 and 288 will fire, each enabling thefollowing SCR to fire in the same manner. When the 0 push button isdepressed, power is supplied to the light emitting diode 290 whichlights to signify that the correct combination has been introduced inthe correct sequence, thereby verifying that the owner of the card hasproperly identified himself.

If the proper combination is not known, particularly if the properpositions for rotary switches 206 and 212 are not known, proper bias cannever be supplied to the card circuit. Even assuming that those properpositions are known, only SCR 272 can be turned on even if all of thepush buttons are depressed. Assuming that SCR 272 was turned on, then ifpush button 9, for example, is depressed, SCR 286 would have no anodevoltage and cannot be fired. Furthermore, the trigger voltage suppliedto the gate of SCR 286 will be coupled through the gate resistor toground and would cause SCR 272 to turn off. Any other wrong sequencewill have the same effect. The reason that the circuit works in thecorrect sequence is that the SCRs, when they have anode voltage, willturn on fast enough to keep the reviously fired portion of the circuitfrom resetting. If any push button other than those numbers whichcomprise the correct combination or code sequence are depressed, thecorresponding SCR will fire since SCR 250, for example, will always haveanode voltage and if button l is depressed SCR 250 will indeed fire. Theoutput of SCRs 250-260, i.e., their cathodes, are all coupled throughline 270, through resistor 296 to the gate of SCR 294. If any outputsare obtained from SCRs 250-260 they will trigger SCR 294 on so thatcurrent will be shunted across the diode 290 thereby preventing it fromturning on. Therefore, even if the proper code sequence was used,pushing any one button corresponding to a number which is not an elementof the sequence, the LED will not light since SCR 294 would be enabled,there being an available anode voltage to it as soon as an output isobtained from SCR 288.

It is necessary that the first SCR of the proper code sequence beimmediately enabled and for that reason the anode of 272 is connecteddirectly to the B+ conductor 266. It would be possible to determineelectrically which is the first digit of the code by determining whichSCR turns on first, and then the next SCR and so on. But, SCRs 250-260are provided to give an additional set of SCRs which can be turned on atany time to further confuse the investigator. These six SCRs willeffectively hide which SCR out of the group 250260 and 272 is thecorrect first digit since any of them can be turned on first. It willalso be noted that any of the six SCRs 250-260 can be turned on oneafter the other and by coupling those SCRs in parallel with essentiallyno load and all having anode voltage it has been found that the SCRswill interact between themselves in random fashion based upon theinherent internal characteristics of each SCR, its relative locationwithin the circuit, the number of other SCRs that have been turned on,etc. In other words, it is possible that all six of the SCRs can beturned on, but in most cases several will be turned on and then when abutton is depressed to turn on an additional one, it may reset one orall of the others in a random fashion which makes an electricalinvestigation of the circuit extremely confusing.

It will thus be seen that the present invention has provided a greatlyimproved method of credit card verification and which will substantiallyreduce credit card misuse. While preferred embodiments of the presentinvention have been shown and described herein, it will be obvious tothose persons skilled in the art that changes and modifications might bemade and it is, therefore, contemplated that such changes andmodifications are within the scope of this invention.

I claim:

1. An improved identity verification system, comprising:

a card, a plurality of contact points situated upon said card, first andsecond circuit means embedded within said card, three or more of saidcontact points being coupled to said first circuit means and providing aunique set of contact points, the remainder of said contact points beingcoupled to said second circuit means;

card reader means comprising contact means for establishing electricalcontact with each of the contact points of said card, third circuitmeans in said reader means, a plurality of selector means electricallycoupled between said contact means and said third circuit means forselectively coupling individual ones of said contact means to said thirdcircuit means; and

indicator means coupled to said first and third circuit means, saidindicator means providing an output signal when said first and thirdcircuit means are coupled together.

2. The system set forth in claim 1 wherein said indicator means includesfirst and second output means, said first output means providing a firstoutput signal when all of said contact points are coupled to said firstcircuit means, and said second output means providing a second outputsignal when any of said contact points are coupled to said secondcircuit means.

3. The system set forth in claim 1 wherein said first circuit meanscomprises a three terminal semiconductor device.

4. The system set forth in claim 1 wherein said first circuit meanscomprises a unijunction transistor.

5. The system described in claim 1 wherein said first circuit meanscomprises a NAND gate.

6. The system described in claim 3 wherein said second circuit meanscomprises a plurality of diodes coufi J pled in randomly-orientedfashion between various of said contact points.

7. The system described in claim 1 wherein:

said first circuit means comprises a unijunction transistor, the threeterminals of which are connected to three individual ones of saidcontact points; and

said second circuit means comprises a plurality of diodes coupled inrandomly-oriented fashion between all the remaining ones of said contactpoints.

8. The system described in claim 1 wherein:

said first circuit means comprises a NAND gate having two inputterminals, one output terminal and two bias terminals, each of saidterminals being connected to individual ones of said contact points; and

said second circuit means comprises a plurality of diodes coupled inrandomly-oriented fashion between all the remaining ones of said contactpoints.

9. The system described in claim 1 wherein:

said first circuit means comprises a first plurality ofsilicon-controlled-rectifiers coupled in series circuit relationship,each of said rectifiers having a gate electrode coupled to one of saidcontact points which define said unique set of points, the last in saidseries of rectifiers having an output conductor coupled to saidindicator means;

said second circuit means comprises a second plurality ofsilicon-controlled-rectifiers coupled in parallel circuit relationship,each of said rectifiers having a gate electrode coupled to one of theremainder of said contact points, said second plurality of rectifiershaving an output conductor coupled to said indicator means.

10. The system set forth in claim 9 were in said indicator meanscomprises a light-emitting diode coupled to the output conductor 7 ofsaid first rectifiers, a silicon-controlled-rectifier coupled inparallel with said diode, said silicon-controlled-rectifier having agate electrode coupled to the output conductor of said second pluralityof rectifiers.

I]. The system described in claim 1 wherein said card reader includesmeans for selectively sensing said contact points, said means comprisingmeans for receiving a card in the reader, contact means in saidreceiving means for contacting each of said contact points, a pluralityof switching means coupled to said contact means for selecting certainones of said contact means according to the aforesaid system of indexnumbers assigned to the contact points on a card, said switching meanshaving indexing means for selecting contact points according to saidseries of code numbers.

12. The system described in claim 11 wherein said indicating means insaid card reading means comprises a fourth circuit means, said fourthcircuit means having first and second output indicating devices, asource of electrical power, means for coupling said source of power tosaid switching means, current responsive means coupled to said switchingmeans and said indicating devices, said current responsive means beingoperative to energize said first output device when said switching meansis coupled only to said first circuit means in a card, said currentresponsive means operative to energize said second output device whensaid switching means is not coupled only to said first circuit means.

13. An improved identity verification system, the combinationcomprising:

a card, first and second circuit means embedded in aid card, a pluralityof contact points upon said card, said contact points disposed in amatrix pattern, said first circuit means being coupled to more than twobut substantially less than all of said contact points, said secondcircuit means being coupled to all of the remaining contact points;

a card reader having means for receiving a card therein, contact meanssituated in said receiving means, said contact means disposed in amatrix pattern adapted to register with the contact points of a card,third circuit means situated in said card reader, selector meanscoupling said third circuit means to said contact means whereby any oneof said contact points of a card may be coupled into said third circuit,said third circuit means including indicator means, said third circuitmeans being operative to provide an output at said indicator means whensaid selector means has been actuated to couple only said first circuitmeans to said third circuit means.

14. An improved identification card and a system for verificationthereof comprising, in combination:

a card comprising at least two lamina adhered together, said card havinga matrix of electrical contact points disposed upon a surface of one ofsaid laminae, access means formed upon one or more surfaces of said cardfor permitting access to said contact points, a first plurality ofsemiconductor means disposed within said matrix and interconnectingsubstantially all of said contact points in random fashion, one or moresecond semiconductor devices having three or more terminals, saidterminals being connected to individual remaining ones of said contactpoints thereby defining a unique combination of points within saidmatrix;

a card reading apparatus for verifying ownership of said card, saidapparatus having means for receiving a card therein, a plurality ofcontact means situated within said receiving means for making electricalcontact with the aforesaid contact points of said card, selector meanscoupled to said contact means for selecting individual ones of saidcontact points, circuit means coupled to said selector means, saidcircuit means including means responsive to the aforesaid secondsemiconductor devices to produce a unique output signal when saidselector means has been actuated to couple said second semiconductordevices to said circuit means.

15. The system described in claim 12 wherein said current responsivemeans comprises a relaxation oscillator.

16. The system set forth in claim 1 wherein said first and secondcircuit means of said card have portions thereof coupled togethertherein whereby external electrical measurements taken at said contactpoints will not indicate which contact points are unique to said firstcircuit means.

17. The system as set forth in claim 9 wherein said first and secondcircuit means of said card have portions thereof coupled togethertherein whereby exter nal electrical measurements taken at said contactpoints will not indicate which contact points are unique to said firstcircuit means.

a card having a plurality of contact points situated thereon defining amatrix, first and second circuit means embedded within said card, saidfirst circuit thereon defining a matrix, first and second circuit meanscomprising one or more first circuit compomeans embedded within saidcard, said first circuit nents coupled to selected ones of aid contactmeans comprising one or more first circuit compopoints, said selectedcontact points thereby delinnents coupled to selected ones of saidcontact ing a unique code number within said matrix, said points, saidselected contact points thereby definsecond circuit means comprising aplurality of secing a unique code number within said matrix, said ondcircuit components coupled to the remainder second circuit meanscomprising a plurality of secof said contact points of said matrix, saidsecond ond circuit components coupled to the remainder circuitcomponents having individual electrical of said contact points of saidmatrix, said second characteristics substantially similar said firstcircuit circuit components having individual electrical components, saidremainder of contact points coucharacteristics substantially similar tosaid first cirpled to said second components thereby defining cuitcomponents, said remainder of contact points 5 false code numbers withinsaid matrix; coupled to said second components thereby defmcard readingmeans comprising contact means for siing false code numbers within saidmatrix; multaneously establishing electrical contact with card readingmeans comprising contact means for siall of the contact points of saidcard, third circuit multaneously establishing electrical contact withmeans, coded selector means coupled between said all of the contactpoints of said card, third circuit 20 contact means and said thirdcircuit means; and means, coded selector means coupled between saidindicator means coupled to said first and second circontact means andsaid third circuit means, and incuit means, said indicator meansincluding means dicator means coupled to said third circuit meansproviding a visual indicator when said first circuit for indicatingwhether or not said coded selector means has been coupled to said thirdcircuit means means has coupled the contact points of said firstaccording to said unique code number, said visual circuit means withsaid third circuit means accordindication means providing no visualindication ing to said unique code number. whenever any portion of saidsecond circuit means 19. An improved identification card verificationsysis coupled to said third circuit means. tem comprising:

1. An improved identity verification system, comprising: a card, aplurality of contact points situated upon said card, first and secondcircuit means embedded within said card, three or more of said contactpoints being coupled to said first circuit means and providing a uniqueset of contact points, the remainder of said contact points beingcoupled to said second circuit means; card reader means comprisingcontact means for establishing electrical contact with each of thecontact points of said card, third circuit means in said reader means, aplurality of selector means electrically coupled between said contactmeans and said third circuit means for selectively coupling individualones of said contact means to said third circuit means; and indicatormeans coupled to said first and third circuit means, said indicatormeans providing an output signal when said first and third circuit meansare coupled together.
 2. The system set forth in claim 1 wherein saidindicator means includes first and second output means, said firstoutput means providing a first output signal when all of said contactpoints are coupled to said first circuit means, and said second outputmeans providing a second output signal when any of said contact pointsare coupled to said second circuit means.
 3. The system set forth inclaim 1 wherein said first circuit means comprises a three terminalsemiconductor device.
 4. The system set forth in claim 1 wherein saidfirst circuit means comprises a unijunction transistor.
 5. The systemdescribed in claim 1 wherein said first cirCuit means comprises a NANDgate.
 6. The system described in claim 3 wherein said second circuitmeans comprises a plurality of diodes coupled in randomly-orientedfashion between various of said contact points.
 7. The system describedin claim 1 wherein: said first circuit means comprises a unijunctiontransistor, the three terminals of which are connected to threeindividual ones of said contact points; and said second circuit meanscomprises a plurality of diodes coupled in randomly-oriented fashionbetween all the remaining ones of said contact points.
 8. The systemdescribed in claim 1 wherein: said first circuit means comprises a NANDgate having two input terminals, one output terminal and two biasterminals, each of said terminals being connected to individual ones ofsaid contact points; and said second circuit means comprises a pluralityof diodes coupled in randomly-oriented fashion between all the remainingones of said contact points.
 9. The system described in claim 1 wherein:said first circuit means comprises a first plurality ofsilicon-controlled-rectifiers coupled in series circuit relationship,each of said rectifiers having a gate electrode coupled to one of saidcontact points which define said unique set of points, the last in saidseries of rectifiers having an output conductor coupled to saidindicator means; said second circuit means comprises a second pluralityof silicon-controlled-rectifiers coupled in parallel circuitrelationship, each of said rectifiers having a gate electrode coupled toone of the remainder of said contact points, said second plurality ofrectifiers having an output conductor coupled to said indicator means.10. The system set forth in claim 9 werein said indicator meanscomprises a light-emitting diode coupled to the output conductor of saidfirst rectifiers, a silicon-controlled-rectifier coupled in parallelwith said diode, said silicon-controlled-rectifier having a gateelectrode coupled to the output conductor of said second plurality ofrectifiers.
 11. The system described in claim 1 wherein said card readerincludes means for selectively sensing said contact points, said meanscomprising means for receiving a card in the reader, contact means insaid receiving means for contacting each of said contact points, aplurality of switching means coupled to said contact means for selectingcertain ones of said contact means according to the aforesaid system ofindex numbers assigned to the contact points on a card, said switchingmeans having indexing means for selecting contact points according tosaid series of code numbers.
 12. The system described in claim 11wherein said indicating means in said card reading means comprises afourth circuit means, said fourth circuit means having first and secondoutput indicating devices, a source of electrical power, means forcoupling said source of power to said switching means, currentresponsive means coupled to said switching means and said indicatingdevices, said current responsive means being operative to energize saidfirst output device when said switching means is coupled only to saidfirst circuit means in a card, said current responsive means operativeto energize said second output device when said switching means is notcoupled only to said first circuit means.
 13. An improved identityverification system, the combination comprising: a card, first andsecond circuit means embedded in aid card, a plurality of contact pointsupon said card, said contact points disposed in a matrix pattern, saidfirst circuit means being coupled to more than two but substantiallyless than all of said contact points, said second circuit means beingcoupled to all of the remaining contact points; a card reader havingmeans for receiving a card therein, contact means situated in saidreceiving means, said contact means disposed in a matrix pattern adaptedto register with the contact points of a card, third circuit meanssituAted in said card reader, selector means coupling said third circuitmeans to said contact means whereby any one of said contact points of acard may be coupled into said third circuit, said third circuit meansincluding indicator means, said third circuit means being operative toprovide an output at said indicator means when said selector means hasbeen actuated to couple only said first circuit means to said thirdcircuit means.
 14. An improved identification card and a system forverification thereof comprising, in combination: a card comprising atleast two lamina adhered together, said card having a matrix ofelectrical contact points disposed upon a surface of one of saidlaminae, access means formed upon one or more surfaces of said card forpermitting access to said contact points, a first plurality ofsemiconductor means disposed within said matrix and interconnectingsubstantially all of said contact points in random fashion, one or moresecond semiconductor devices having three or more terminals, saidterminals being connected to individual remaining ones of said contactpoints thereby defining a unique combination of points within saidmatrix; a card reading apparatus for verifying ownership of said card,said apparatus having means for receiving a card therein, a plurality ofcontact means situated within said receiving means for making electricalcontact with the aforesaid contact points of said card, selector meanscoupled to said contact means for selecting individual ones of saidcontact points, circuit means coupled to said selector means, saidcircuit means including means responsive to the aforesaid secondsemiconductor devices to produce a unique output signal when saidselector means has been actuated to couple said second semiconductordevices to said circuit means.
 15. The system described in claim 12wherein said current responsive means comprises a relaxation oscillator.16. The system set forth in claim 1 wherein said first and secondcircuit means of said card have portions thereof coupled togethertherein whereby external electrical measurements taken at said contactpoints will not indicate which contact points are unique to said firstcircuit means.
 17. The system as set forth in claim 9 wherein said firstand second circuit means of said card have portions thereof coupledtogether therein whereby external electrical measurements taken at saidcontact points will not indicate which contact points are unique to saidfirst circuit means.
 18. An improved identification card verificationsystem comprising: a card having a plurality of contact points situatedthereon defining a matrix, first and second circuit means embeddedwithin said card, said first circuit means comprising one or more firstcircuit components coupled to selected ones of said contact points, saidselected contact points thereby defining a unique code number withinsaid matrix, said second circuit means comprising a plurality of secondcircuit components coupled to the remainder of said contact points ofsaid matrix, said second circuit components having individual electricalcharacteristics substantially similar to said first circuit components,said remainder of contact points coupled to said second componentsthereby defining false code numbers within said matrix; card readingmeans comprising contact means for simultaneously establishingelectrical contact with all of the contact points of said card, thirdcircuit means, coded selector means coupled between said contact meansand said third circuit means, and indicator means coupled to said thirdcircuit means for indicating whether or not said coded selector meanshas coupled the contact points of said first circuit means with saidthird circuit means according to said unique code number.
 19. Animproved identification card verification system comprising: a cardhaving a plurality of contact points situated thereon defining a matrix,first and second circuit means embedded wIthin said card, said firstcircuit means comprising one or more first circuit components coupled toselected ones of aid contact points, said selected contact pointsthereby defining a unique code number within said matrix, said secondcircuit means comprising a plurality of second circuit componentscoupled to the remainder of said contact points of said matrix, saidsecond circuit components having individual electrical characteristicssubstantially similar said first circuit components, said remainder ofcontact points coupled to said second components thereby defining falsecode numbers within said matrix; card reading means comprising contactmeans for simultaneously establishing electrical contact with all of thecontact points of said card, third circuit means, coded selector meanscoupled between said contact means and said third circuit means; andindicator means coupled to said first and second circuit means, saidindicator means including means providing a visual indicator when saidfirst circuit means has been coupled to said third circuit meansaccording to said unique code number, said visual indication meansproviding no visual indication whenever any portion of said secondcircuit means is coupled to said third circuit means.